In modern societies, electronic products become indispensable parts in human lives. The electronic products are applied in many sectors, including food, clothing, housing, transportation, education and entertainment. For facilitating carrying and using electronic products, the trends of designing electronic products are toward light weightiness and slimness. Generally, the electronic product is equipped with a keyboard. In case that the keyboard device is a mechanical keyboard, the mechanical keyboard has various shafts. The shafts are classified according to their colors. For example, these colors include a blue color, a red color, a black color, a brown color and a green color. The shafts of the mechanical keyboard with different colors require different actuation forces and generate different click sounds. Consequently, the mechanical keyboard generates different clicking sensations. Moreover, because of the proper click sound and the proper actuation force, the suitable typing rhythm of the user can be maintained.
For allowing the electronic product to meet the requirements of light weightiness and slimness, it is necessary to simplify the arrangement of a support structure or an elastic structure of the keyboard structure or reduce the height of the supporting structure to reduce the overall volume of the keyboard structure. In other words, the structure of the slim keyboard is usually not equipped with the shafts of the mechanical keyboard. Under this circumstance, it is difficult for the slim keyboard to generate the proper click sound. However, since the user is unable to immediately realize whether the pressing action of the slim keyboard is completed or the uncomfortable tactile feel is generated, it is difficult to maintain the suitable typing rhythm of the user.
For solving the above drawbacks, it is necessary to simplify the keyboard structure while generating the proper click sound. For example, a keyboard structure is disclosed in U.S. Pat. No. 9,767,970. The keyboard structure comprises a keycap, a supporting plate and a scissors-type connecting element. A protrusion part is protruded from a bottom surface of the keycap. An elastic structure is disposed on the supporting plate and aligned with the protrusion part. While the keycap is moved downwardly, the protrusion part is moved toward the elastic structure. Since the elastic sheet is collided by the protrusion part, a click sound is generated. However, this keyboard structure still has some drawbacks. For example, since the protrusion part is protruded from the bottom surface of the keycap, the original coupling position between the keycap and the scissors-type connecting element is possibly changed. Moreover, the arrangement of the protrusion part increases the complexity of assembling the keyboard. Moreover, since the protrusion part is protruded from the bottom surface of the keycap, a material embrittlement problem occurs. If the keyboard structure is frequently pressed, the protrusion part is readily suffered from breakage or damage. Under this circumstance, the keyboard structure cannot generate the proper click sound.
For overcoming the above drawbacks, there is a need of providing a keyboard structure that has a simplified design and is easily assembled. When the keyboard structure is pressed, the proper click sound can be stably and continuously generated.